TAO/examples/Event_Comm/Event_Comm.idl

   1 /* -*- C++ -*- */
   2
   3 //=============================================================================
   4 /**
   5  *  @file    Event_Comm.idl
   6  *
   7  *  The CORBA IDL module for distributed event notification.
   8  *
   9  *
  10  *  @author Douglas C. Schmidt (d.schmidt@vanderbilt.edu) and Pradeep Gore (pradeep@cs.wustl.edu)
  11  */
  12 //=============================================================================
  13
  14
  15 #if !defined (_EVENT_COMM_IDL)
  16 #define _EVENT_COMM_IDL
  17
  18 module Event_Comm
  19 {
  20   // = TITLE
  21   //   The CORBA IDL module for distributed event notification.
  22
  23   struct Event
  24   {
  25     // = TITLE
  26     //   Defines the interface for an event <Event>.
  27     //
  28     // = DESCRIPTION
  29     //   This is the type passed by the Notifier to the Consumer.
  30     //   Since it contains an <any>, it can hold any type.  Naturally,
  31     //   the consumer must understand how to interpret this!
  32
  33     string tag_;
  34     // Tag for the event.  This is used by the <Notifier> to compare
  35     // with the <Consumer>s' filtering criteria.
  36
  37     any value_;
  38     // An event can contain anything.
  39
  40     Object object_ref_;
  41     // Object reference for callbacks.
  42   };
  43
  44   interface Consumer
  45   {
  46     // = TITLE
  47     //   Defines the interface for a <Consumer> of events.
  48
  49     void push (in Event event_instance);
  50     // Inform the <Consumer> that <event> has occurred.
  51
  52     void disconnect (in string reason);
  53     // Disconnect the <Consumer> from the <Notifier>,
  54     // giving it the <reason>.
  55   };
  56
  57   interface Notifier
  58   {
  59     // = TITLE
  60     //   Defines the interface for a <Notifier> of events.
  61
  62     exception CannotSubscribe
  63     {
  64       // = TITLE
  65       //   This exception in thrown when a <subscribe> fails.
  66
  67       string reason_;
  68     };
  69
  70     exception CannotUnsubscribe
  71     {
  72       // = TITLE
  73       //   This exception in thrown when a <unsubscribe> fails.
  74
  75       string reason_;
  76     };
  77
  78     // = The following operations are intended for Suppliers.
  79
  80     void disconnect (in string reason);
  81     // Disconnect all the receivers, giving them the <reason>.
  82
  83     void push (in Event event_instance);
  84     // Send the <event> to all the consumers who have subscribed and
  85     // who match the filtering criteria.
  86
  87     // = The following operations are intended for Consumers.
  88
  89     void subscribe (in Consumer subscriber,
  90                     in string filtering_criteria) raises (CannotSubscribe);
  91     // Subscribe the <Consumer> to receive events that match the
  92     // regular expresssion <filtering_criteria> applied by the
  93     // <Notifier>.  If <filtering_criteria> is "" then all events are
  94     // matched.
  95
  96     void unsubscribe (in Consumer unsubscriber,
  97                       in string filtering_criteria) raises (CannotUnsubscribe);
  98     // Unsubscribe the <Consumer> that matches the filtering criteria.
  99     // If <filtering_criteria> is "" then all <Consumers> with the
 100     // matching object reference are removed.
 101   };
 102 };
 103
 104 #endif /* _EVENT_COMM_IDL */